2012 Fiscal Year Final Research Report

Elucidation of cooperative binding of oxygen to hemoglobin from the standpoint of the electronic theory of the heme cofactor

Research Project

Project/Area Number	23655151
Research Category	Grant-in-Aid for Challenging Exploratory Research
Allocation Type	Multi-year Fund
Research Field	Chemistry related to living body
Research Institution	University of Tsukuba
Principal Investigator	YAMAMOTO Yasuhiko 筑波大学, 数理物質系, 教授 (00191453)
Co-Investigator(Kenkyū-buntansha)	TAI Hulin 筑波大学, 数理物質系, 特任助教 (40512554)
Project Period (FY)	2011 – 2012
Keywords	ヘムタンパク質 / ヘム電子構造 / 計算化学 / NMR / 機能解析 / π-π相互作用タンパク質の高次構造 / マリケン電荷
Research Abstract	Hemoglobin is the heme-containing oxygen-transport protein in the red blood cell. Highly efficient oxygen-transport of hemoglobin is achieved by cooperative oxygen binding properties of the protein. In this study, molecular mechanism responsible for the cooperative oxygen binding of the protein has been investigated from the standpoint of a novel theory, i.e., the electron theory of the heme cofactor. The study revealed that electronic interaction among the heme π-system, the heme iron, and the F-bound histidine plays a crucial role in control of the cooperative oxygen binding of the protein.